Embossed plastic surface covering and method of preparing same

ABSTRACT

A chemically embossed vinyl-chloride resin sheet material is prepared by treating certain areas of the gelled surface of a vinyl-chloride plastisol containing a blowing agent with a liquid containing a carboxylated vinyl-chloride resin and a heatreactive compound, such as an amide reactive with the carboxyl groups of the resin, and heating the treated gelled vinylchloride resin sheet material to a temperature sufficient to react the amide with the carboxylated vinyl-chloride resin to cross-link the resin, to decompose the blowing agent and to fuse the vinyl-chloride resin plastisol after expansion, whereby a chemically embossed product is produced due to inhibition of full expansion of the sheet material by the cross-linked carboxylated vinyl-chloride resin in the treated areas.

United States Patent [19 Crowley Nov. 27, 1973 [54 EMBOSSED PLASTICSURFACE COVERING AND METHODOF PREPARING SAME [76] Inventor: Richard P.Crowley, 125 High St.,

Boston, Mass. 02110 [22] Filed: Apr. 24, 1972 [21] Appl. No.: 246,722

Related US. Application Data [63] Continuation-in-part of Ser. No.43,233, June 3, 1970, Pat. No. 3,671,283, and a continuation-in-part ofSer. No. 228,396, Feb. '22, 1972, Continuation of Ser. No. 28,052, April13, 1970, abandoned, Continuation-impart of Ser. No. 566,810, July 21,1966, Pat. No. 3,519,527, which is a continuation-in-part of Ser. No.541,100, April 8, 1966, Pat. No. 3,453,171.

3,574,659 4/1971 Kwart et al. 161/160 Primary Examiner-William J. VanBalen [5 7] ABSTRACT A chemically embossed vinyl-chloride resin sheetmaterial is prepared by treating certain areas of the gelled surface ofa vinyl-chloride plastisol containing a blowing agent with a liquidcontaining a carboxylated vinyl-chloride resin and a heat-reactivecompound, such as an amide reactive with the carboxyl groups of theresin, and heating the treated gelled vinyl-chloride resin sheetmaterial to a temperature sufficient to react the amide with thecarboxylated vinyl-chloride resin to cross-link the resin, to decomposethe blowing agent and to fuse the vinyl-chloride resin plastisol afterexpansion, whereby a chemically embossed product is produced due toinhibition of full expansion of the sheet material by the cross-linkedcarboxylated vinyl-chloride resin in the treated areas.

16 Claims, No Drawings EMBOSSED PLASTIC SURFACE COVERING AND METHOD OFPREPARING SAME REFERENCE TO PRIOR APPLICATIONS tinuation-in-part of Ser.No. 541,100, filed Apr. 8,

1966 (now US. Pat. No. 3,453,171).

BACKGROUND OF THE INVENTION There are a number of methods of impartingan embossed appearance to a cellular sheet, including both chemicallyand mechanically embossed techniques. Chemical embossing includesmethods for raising or lowering the decomposition temperature of theblowing agent used, and methods for preferentially stiffening prior toexpansion certain areas of the expandable resin sheet. v

US. Pat. No. 3,365,353 incorporates a monomer into a vinyl-chlorideplastisol which is subsequently formed into a gelled resin sheet. Aliquid containing a peroxide catalyst is then applied in a predeterminedpattern to one surface of the gelled sheet. The treated sheet is thenheated to polymerize the monomer, to decompose the blowing agent and tofuse the cellular plasticized resin, thereby providing a chemicallyembossed product.

US Pat. Nos. 3,293,094 and 3,293,108 provide a method of chemicalembossing by alteration of the decomposition temperature of the chemicalblowing agent in the treated areas by the use of certain compounds.

US. Pat. No. 3,453,171 provides a chemically ernbossed product bypreventing the full expansion of a gas-expandable resin in certaintreated areas by the use of a cross-linking agent for the resin whichmay be a peroxide or a beam of atomic or subatomic particles.

US. Pat. No. 3,458,337 provides achemically embossed sheet by employingan agent which suppresses the catalytic action of an organozinc catalystcontained in the gas-expandable resin sheet.

US. Pat. No. 3,538,204 obtains a chemically embossed product by applyingan acrylic monomer and a peroxide cross-linking agent for the monomer toa gelled surface of a gas-expandable vinyl-chloride resin in a printingink composition, and, subsequently, heating the material to effectpolymerization of the monomer in the treated areas.

SUMMARY OF THE INVENTION My invention concerns an improved method ofpreparing chemically embossed cellular sheet products, such as floortile, and to the products so produced. In particular, my inventionrelates to a method of preparing a chemically embossed cellularvinyl-chloride resin floor tile by applying to the gelled surface of thegasexpandable vinyl-chloride resin a cross-linkable vinylchloride resinand a heat-reactive product which reacts with the cross-linkable resin,thereby, on heating and cross-linking of the resin, producing achemically embossed product.

My method comprises: applying to the surface of a gas-expandablethermoplastic resin a polymer containing, for example, interpolymerizedor pendant reactive groups in the polymer, and a compound which reactswith the polymer groups to cross-link the polymer; and heating thetreated thermoplastic resin to cross-link the polymer through suchreaction, thereby providng a chemically embossed product throughpreventing full expansion of the resin in the treated areas.

In particular, my method comprises: casting a vinylchloride resinplastisol containing a blowing agent into a thin layer; heating the castplastisol layer to a temperature sufficient to form a gelled layer, butinsufficient to decompose the blowing agent; applying to the gelledplastisol surface a liquid containing a cross-linkable vinyl-chlorideresin, such as a vinyl-chloride resin containing hydroxyl, carboxyl oramide groups, and a heatreactive amide or other compounds to react withthe reactive groups of the resin; permitting the liquid to penetrate thegelled layer to the desired depth; and heating the treated gelled resinlayer to a temperature to provide for cross-linking of the resin groupswith the heat-reactive compound to harden the treated areas, todecompose the-blowing agent and to fuse the resulting cellularvinyl-chloride resin, thereby providing a cellular product havingchemically embossed areas where full expansion of the resin is preventedin thetreated areas. 7

In the method described, typically azodicarbonamide is commonly employedas a blowing agent; however, as will be recognized by those skilled inthe art, a variety of blowing or expanding agents, liquid and solid,alone or in combination, may be employed to provide the gas-expandablesheet material. Further, the temperatures employed to obtain a gelledvinyl-chloride resin layer are, for example, about to 160 C; e.g., to-C, while decomposition of the blowing agent and fusion of thevinyl-chloride resin is often accomplished at temperatures ranging fromabout to 230 C; e.g., to C. My method may be adopted for the productionof laminate-type sheet materials, such as cellular floor tiles, whereina gasexpandable thermoplastic resin layer is cast or laminated onto asupporting sheet material, such as a woven or nonwoven fibrous ornonfibrous scrim or base sheet;

for examp1e,a resin-reinforced asbestos sheet or glass fiber, etc..Optionally, a transparent wear-resistant thin resin top layer may beapplied, either before or after expansion, but preferably, beforeexpansion. My method will be described in particular in connection withthe production of a floor tile product; however, it may be usefullyemployed to produce a variety of chemically embossed cellular productsto include wall or upholstery covers, garments, boots, shoes, handbagsand other cellular materials in which a chemically embossed design isdesired.

The thermoplastic resin suitable for use in my invention includes, butis not limited to, those gasexpandable organic thermoplastic resinousmaterials, such as those polymers and copolymers of vinyl resins likevinyl-chloride resins to include polyvinyl chloride and copolymers ofvinyl chloride with short-chain fatty acids of vinyl esters, such asvinyl acetate or vinylidene chloride, vinylbutyrate and such materialsas well as olefinic resins, such as C -C olefinic resins ofpolypropylene, polyethylene, ethylene-propylene copolymers andterpolymers and other thermoplastic materials.

The thermoplastic resins may be suitably plasticized, such as by the useof ester-type plasticizers like adipates, sebacates, phthalates, etc.,and may contain those other additives normally employed, such as metalsalt stabilizers, fillers, pigments, dyes, solvents, secondaryplasticizers, viscosity-control additives, thickeners, glycols,cell-control agents and the like. The selection of the blowing agent tobe employed depends upon the melt viscosity index and other propertiesof the polymer and the fonnulation, which blowing agents and theirselections are well known.

The reactive polymers useful in my method may be selected to becompatible or imcompatible with the thermoplastic resin surface to betreated. Often, it is preferred that a similar polymer be employed forthe purposes of compatability, such as, for example, employing acarboxylated vinyl-chloride resin as the reactive polymer with a gelledvinyl-chloride resin, while the employment of incompatible polymers maybe used where distinct design effects are desired. The amount and typeof reactive polymer and the heat-reactive polymer to cross-link thereactive groups of the polymers may be varied as desired. Depending uponthe degree of chemical embossing desired; that is, upon the degree ofhardness or stiffness in the treated areas, the reactive polymer may befully or partially cross-linked, such as, for example, by varying theamount and nature of the heat-reactive cross-linking material.

The reactive polymer and the heat-reactive compound are typicallyapplied to the treated area as a part of a liquid, either in aplastisol, organosol, or in a solvent solution, or in such form as topermit the liquid or polymer and reactive compound to penetrate into thegas-expandable thermoplastic resin. Often, both the reactive polymer andheat-reactive compound are incorporated into a printing ink compositionso that the surface of the gas-expandable resin sheet material may beprinted with the desired design effect, and treated in the same step.Such printing-ink composition may contain solvents, such as volatileorganic solvents, as well as diluents, pigments, dyes, stabilizers,plasticizers and other additives. Organic solvent or plasticizer liquidcompositions are preferred in order to permit rapid penetration of thegas-expandable resin sheet material in the treated areas. Typicalorganic solvents which may be employed would include, but not be limitedto: hydrocarbon, such as tetrahydrofurane, benzene, xylene, toluene,cyclohexanone, heptane, as well as ketones, aldehydes, esters andalcohols, such as acetone, methylethyl ketone, ethanol, isopropanol,methyl isobutyl ketone, and other such volatile solvents commonlyemployed in solvent-printing inks, as well as liquid plasticizers.Variation in the degree of penetration of the liquid composition may beaccomplished by varying the type and amount of solvent or liquidemployed, as well as the time of penetration. in a production process, amore powerful solvent and penetration action is often desired in orderto reduce the time of penetration, say, for example, from 1 to minutes,while if time permits aging of the gas-expandable sheet after treatmentin certain instances, 30 minutes to 12 hours often provides deeperembossing effects.

In the preferred method of treating the gasexpandable thermoplasticresin surface, both the reactive polymer and the heat-reactive compoundare applied to the surface in the same liquid composition. However, thereactive polymer may be included in the gas-expandable thermoplasticresin sheet material, and for example, may comprise all or part of suchsheet material, or the heat-reactive compound likewise be incorporated,say, as an additive to the gas-expandable thermoplastic resin sheetmaterial. However, these nonpreferred techniques are wasteful of themore expensive reactive polymer and heat-reactive material.

ln my method, the reactive polymer and the reactive material should notreact at room temperature or a temperature at which the material or thecompositions may be stored, but should be reactive at above, forexample, 50 C, or even C, in order to prevent premature cross-linking ofthe polymer. Typically, reaction should occur below, at orsimultaneously with the gas-expansion of the resin sheet materialtreated. it is preferred that the reaction occur prior to anysubstantial gas-expansion of the treated sheet material. For example,with a vinyl-chloride resin sheet material containing azodicarbonamideas the blowing agent, the cross-linking reaction should occur below 140C, typically from 90 to C.

The reactive polymers employed in the practice of my invention are wellknown, and may be those polymers which contain reactive groups (e.g.,interpolymerized or pendant) capable of reacting with a heatreactivecompound to cross-link the polymer, and to provide for an increase inmolecular weight and/or melt viscosity of the resulting cross-linkedpolymer. My reactive polymers do not include monomers which are subjectto polymerization through the use of peroxide cross-linking agents, andthe polymerization reaction of the monomers through their unsaturatedlinkages or in block fashion, through the use of heat-reactive compoundswhich induce cross-linking between reactive groups of the respectivepolymers and the cross-linking compound. Typical polymer-functionalgroups which serve as reactive groups would include, but not be limitedto, hydroxyl, carboxyl, sulfonyl and amide groups. The employment of across-linked reactive polymer provides for improved chemical embossingwith lower amounts of polymers over the use of monomers which arepolymerized through peroxide-type catalysts, since cross-linking ofpolymers provides for a more rapid increase in molecular weight and meltviscosity in the treated areas than the polymerization of monomers,particularly where the monomers are of low molecular weight and appliedin small amounts.

Some examples of reactive polymers containing a hydroxyl functionalgroup would include: copolymers of hydroxyalkylmethacrylate, such asethyl and propyl hydroxymethacrylate, and methylol acrylamides, such asN-methylol acrylamide; alkyl resins, polymerized epoxides; polyvinylalcohol and alkylated polyvinyl alcohol; acrylated cellulose derivativesand the like. Typical examples of reactive polymers containing acarboxyl reactive group would include: copolymers of acrylic ormethacrylic acid; alkyl resins; carboxylated cellulose derivatives; andcarboxylated vinyl halide resins. The carboxyl groups may be present ina free-acid form or also may be present as an amine, ammonium or othersalt form wherein free carboxyl is regenerated when the salt is heated.Typical examples of amide groups in reactive polymers would include:copolymers of acrylamide or methacrylamide; reactive polymers composedof acrylic, vinyl halide or copolymerized acrylic vinyl halide monomers,such as hydroxyalkylmethacrylatevinyl chloride, acrylamide ormethacrylamide-vinyl chloride, and/or copolymers of acrylic ormethacrylic acids with vinyl halides. Reactive vinyl halide resins arethe preferred reactive polymers for employment in my invention.

Typical reactive vinyl-halide resins include the homo and copolymerresins, such as vinyl chloride and copolymers with short-chainunsaturated fatty acids like vinyl acetate, as well as polyvinylchloride. Carboxylated vinyl-halide resins may be prepared byinterpolymerizing with or reacting the monomer in the presence of orblending with an unsaturated sulfonic or carboxylic acid. Typical acidswhich may be employed would include short-chain unsaturated carboxylicacids, such as alpha-beta C C unsaturated aliphatic mono or dicarboxylic acids, like acrylic acid, methacrylic acid, itaconic acid,fumaric acid, maleic acid, and their salts, including the amine andammonium salts and anhydrides where applicable. A reactive polymer, forexample, vinyl-chloride resin, may contain from about 0.5 to 25 partsper hundred parts of the resin (phr) of the reactive groups; e. g., theunsaturated carboxylic acid; for example, from 1 to 10 parts. Thecarboxylic acids employed may include the higher moleculardisperson-type resins so that the particles may be dispersed in aplasticizer or in a combination of primary and secondary plasticizers ina plastisol or in an organosol. e

The preferred reactive vinyl-halide resins of my invention include thecarboxylated vinyl-chloride resins or the amine or ammonium salts ofsuch resins. Reactive polymers containing hydroxyl, carboxylic andamide-reactive groups may be reacted with a heatreactive cross-linkingcompound, such as an amide; for example, with a heat-reactive compound,such as a melamine resin, like a butylated melamineformaldehyde resin orhexamethoxymethylmelamine. An acid catalyst is usually required for thereaction of the hydroxyl and amide groups, while typically thecarboxylic groups of the carboxylated resins are sufficiently acidic toprovide self-catalysis; although, of course, additional acid catalystmay be used to further accelerate the cross-linking where desired.

A variety of heat-reactive compounds to cross-link the reactive polymersmay be employed in connection I with my method, which, heat-reactivecompounds are well known. Such heat-reactive compounds would include,but not belimited to: amino resins, such as melamine-formaldehyde andurea-formaldehyde resins, phenol-formaldehyde resins, as well as epoxycompounds and polyisocyanates, such as diisocyanate and isocyanateamides. Specific amide compounds would includehexarnethoxymethylmelamine, dicyandiamide, butylatedmelamine-formaldehyde resins and similar compounds. These latter amidecompounds react while at elevated temperatures while maintaining goodstorage stability in the presence of the reactive polymer at roomtemperature. More particularly, carboxylated vinyl-chloride resins maybe cross-linked with ureaformaldehyde esters, diepoxides,trimethylolphenol, tris 1-2 methylazirdinylphosphazene oxide, and soforth, while hydroxylated vinyl-chloride resins may be cross-linked withurea-formaldehyde esters, toluene diisocyanate and the like.

The amounts of heat-reactive cross-linking compounds to be employeddepend upon the number of reactivegroups and the degree of cross-linkingdesired, but typically, may range from about 0.1 to parts per hundredparts of the reactive resin; for example, 0.5 to 5.0 parts. The degreeof cross-linking should be balanced between the desired melt resistanceand thermoplasticity required. All of the cross-linking of the reactivepolymer need not occur prior to the decomposition of the blowing agent,and, in fact, often residual crosslinking effects will occur on heatingto the fusing temperature and on aging at a higher temperature. Where areactive compound, such as a carboxylated vinylchloride resin, isemployed in a liquid composition, such as a printing ink, amounts of thehigh molecular weight disperson reactive resin often range from 10 to50% by weight of the composition.

DESCRIPTION OF THE PREFERRED EMBODIMENTS For the purposes ofillustration only, my method will be described in connection with thechemical embossing of a vinyl-chloride resin sheet material.

EXAMPLE 1 The gas-expandable thermoplastic resin formulation and thetransparent formulation employed are as follows:

Base Coat Formulation A solvent-type printing ink composition containinga mixture of a vinyl-chloride resin and a carboxylated modifiedvinyl-chloride resin is employed in a liquid formulation as follows:

1. Vinyl chloride-vinyl acetate (940%) copolyrner dispersion low fusionresin "2. Disperson grade carboxyl modified dispersion resin; e.g.,vinyl chloride-vinyl acetate copolymer resin containing reactiveunsaturated carboxylic acid groups (GEON X30 X 17 a Trademark of B.F.Goodrich Chemical Company) 3. Plasticizer primary cresyldiphenylphosphate 4. Plasticizer secondary epoxidized soybean oil 5. PigmentAntimony Trioxide (71.4% in dioctyl phthalate Y 6 6. StabilizerBarium-cadmium fatty acid soap 6 7. Cross-linking carboxylic reactivecompound Dicyandiamide (67.5% pulverized grade dispersion in dioctylphthalate) l0 8. Methylethyl ketone 20 9. Dioxane 25 i0. Pigment andfiller as required 0.5 to I00 Average carboxyl content 1.67 grams per100 grams of resin The base coat plastisol is cast into a supportingsheet material, such as resin-reinforced asbestos sheet material or aglass fiber scrimmaterial, in a thin wet film layer of about 10 to 50mils, and then heated to a temperature sufficient to gel the plastisolwithout decomposition of the blowing agent; for example, 100 to 135 Cfor 3 to 15 minutes. The above printing ink composition is then appliedin a predetermined pattern, such as by the employment of adesign-embossed or engraved printing roll, to the top surface of thegelled base plastisol. The liquid is allowed to penetrate into thegelled surface for approximately 1 to 5 minutes. The treated sheet isthen heated to a temperature of 120 to 140 C for l to 15 minutes toeffect the cross-linking of the carboxylated resin with the amide in thetreated areas. The top coat plastisol is then cast in a thin wet layerfrom about 1 to mils onto the treated gelled surface. The top coatformulation represents on fusing a transparent wear-resistant layer. Ifdesired, the top coat formulation may be cast after treating the surfaceand the cross-linking of the carboxylated resin and gelling and fusingof the top coat cariied out in one step. The sheet material is thenheated in a hot-air oven which may contain infrared heaters to atemperature of 170 to 200 C for 3 to minutes. On such heating, thecarboxylated resinmay be further cross-linked, the blowing agent isdecomposed, expanding the base plastisol to a cellular layer, andproviding for the fusion of the cellular layer so formed. Due to thecross-linking of the carboxylated resin in the treated areas, this arearesists full expansion; that is, represents the depressed areas of thesheet, which results in a chemically embossed floor tile product.

EXAMPLE 2 The foregoing example for preparing a chemically embossedfloor tile is repeated, except that the following plastisol liquidprinting ink composition is employed in place of the composition ofExample 1:

1. Vinyl chloride maleic ester copolymer resin (PLlOVlC MC-85 aTrademark of the Goodyear Tire and Rubber Co.) 75.00 2. Plasticizercresyldiphenyl phosphate 25.00 3. Plasticizer chlorinated paraffin(43-45% chlorine) 15.00 4. Plasticizer Dioctyl phthalate 26.7 5.Stabilizer Barium-cadmium organic acid salt 1.67 6. Pigment Antimonytrioxide 3.00 7. Hexamethoxymethylmelamine (Cymel 301 American CyanamideCompany) 3.00

EXAMPLE 3 Example 1 is repeated employing in place of the carboxylatedvinyl resins of Examples 1 and 2 a carboxylated vinyl-chloride resincomposed of 83% vinyl chloride, 16% vinyl acetate and about 1% maleicacid (VMCC Union Carbide Corporation). The heatreactive compoundemployed is a butylated melamineformaldehyde resin in an amount of about3 parts per hundred parts of the reactive resin.

EXAMPLE 4 EXAMPLE 5 Example 1 is repeated employing as the reactiveresin an epoxy resin produced by the reaction of bisphenol A andepichlorhydrin. A heat-reactive compound is used in the presence of anacid catalyst employing a formulation such as the following:

Epon 1007 resin (an epoxy resin which is a product of Shell ChemicalCompany) Ethylene glycol ethylether acetate Silicone resin (cell controlagent) Catalyst 1010 (an acid catalyst of American Cyanamidc Company)Methyl-isobutyl ketones Toluene Pigment titanium dioxide 2 Cymel 301hexamethoxymethylmelamine Toluene l EXAMPLE 6 Example 1 is repeatedemploying a hydroxyl reactive acrylic resin employing a paratoluenesulfonic acid as an acid catalyst and butylated benzoguanamine as theheat-reactive compound or a butylated melamineformaldehyde resin.

EXAMPLE 7 Example 1 is repeated employing as the reactive polymer asolvent-soluble acrylic copolymer or tripolymer comprising methacrylate,ethyl acrylate and an acrylic acid with a hexamethoxymethylmelamine asthe heat-reactive compound.

EXAMPLE 8 A carboxylic acrylic resin is employed as the reactivecompound, which resin comprises a copolymer of an unsaturatedmonocarboxylic acid and the alkyl esters of such acid, such as, forexample, acrylic acid and butyl acrylate, which reactive polymer iscross-linked employing a small amount of paratoluene sulfonic acid as anacid catalyst, and hexamethoxymethylmelamine as the heat-reactivecompound.

EXAMPLE 9 A reactive polymer is employed in the liquid-carrierformulation which comprises an alkyl resin which is produced from acombination of phthalic anhydiide or trimellitic anhydride, adipic andvarious polyols with fatty acids as an optional feature. These reactivealkyl resins may be cross-linked by hexamethoxymethylmelamine.

EXAMPLE 10 Example 1 is repeated employing polyvinyl esters and acetyls;for example, partially hydrolized polyvinyl acetate, in the presence oflow concentration of hydrochloric or sulfuric acid withhexamethoxymethylmelamine employed as the heat-reactive compoundprovides a cross-linked vinyl acetate.

EXAMPLE 1 1 Vinyl acetate-chloride copolymers, such as, for example,vinyl DHEH (a product of Union Carbide Corporation) and 50% dialkylphthalate as the plasticizer may be employed as a liquid-carriercomposition to treat certain areas in the presence of l phr of acidcatalyst 1010 and about 5 parts of Cymel 301, which composition whenheated for to 20 minutes at 375 F cross-links the resin.

EXAMPLE 12 The chemically embossing technique of Example 1 is repeated,except that the carboxylated vinyl-chloride resin is employed in anamount of from about 10 to 35% in the base formula plastisol, and nocarboxylated resin is employed in the liquid-carrier composition,although the liquid-carrier composition comprises the heat-reactivecompound, thereby producing a chemically embossed product in the treatedareas, while the carboxylated vinyl-chloride resin in the untreatedareas remains unchanged.

My invention has been described employing various illustrative reactivepolymers and heat-reactive compounds to cross-link the polymers;however, it is apparent to a person skilled in the art that variousmodifications, additions and changes to such formulations and techniquesmay be made, all within the spirit of the scope of my invention.

What I claim is:

l. A method of preparing a cellular thermoplastic resin material havingan embossed effect on the surface, which method comprises:

a. applying to selected areas of a gas-expandable thermoplastic resinousmaterial a polymer containing reactive groups consisting of hydroxyl,carboxyl or amide groups, and a heat-reactive compound which will reactand cross-link with said reactive groups of the polymer to reduce thethermoplastic properties of the resinous material in the selected areas;and

b. heating the resinous material to effect the crosslinking of thepolymer and to expand the resinous material, whereby full expansion ofthe resinous material in the selected areas is inhibited by thecross-linked polymer.

2. The method of claim 1 wherein the reactive polymer is avinyl-chloride resin or acrylic resin, an alkyl resin or vinyl-acrylicresin, or an epoxy resin.

3. The method of claim 1 wherein the heat-reactive compound is an amide.

4. The method of claim 3 wherein the heat-reactive compound is an amideselected from the group consisting of melamine-formaldehyde resin,dicyanamide or hexamethoxymethylmelamine.

5. The method of claim 1 wherein the thermoplastic resinous material isa plasticized vinyl-chloride resin which contains a chemical blowingagent therein.

6. The method of claim 1 wherein the heat-reactive compound is presentin an amount of from about 0.1 to 15 phr of the polymer, and the polymercontains from about 0.5 to 25 phr of the reactive groups.

7. The method of claim 1 which includes applying the polymer andheat-reactive compound to the selected areas in a liquid printingcomposition.

8. The method of claim 1 wherein cross-linking of the heat-reactivecompound and the polymer occurs at a temperature of from 50 to C.

9. The method of claim 1 which includes crosslinking the polymer withthe heat-reactive compound in the presence of an acid catalyst in anamount of from about 0.05 to 2.0 phr.

10. The cellular chemically embossed product produced by the method ofclaim 1.

11. A method of preparing a cellular embossed thermoplastic resin, whichmethod comprises:

a. applying to a selected area'of a gas-expandable gelled vinyl-chlorideresin sheet material a vinylchloride polymer containing reactivehydroxyl, carboxyl or amide groups, and a heat-reactive amide compoundwhich will react with the groups to cross-link the polymer, and toreduce the thermoplasticity of the gas-expandable vinyl-chloride resinin the selected areas; and

b. heating the gas-expandable vinyl-chloride resin to a temperature toeffect the cross-linking of the vinyl-chloride polymer, the decomposingof the blowing agent and the fusing of the expanded vinylchloride resin,thereby producing a chemically embossed cellular product.

12. The method of claim 11 which includes applying the polymer and theheat-reactive amide cross-linking compound in a liquid plastisolcomposition to the surface of the gelled gas-expandable thermoplasticresin material.

13. The method of claim 11 which includes incorporating the polymer inthe gas-expandable thermoplastic resin material and treating selectedareas with the heatreactive amide compound.

14. The method of claim 11 which includes incorporating in thegas-expandable thermoplastic resin material a cross-linking amount ofthe heat-reactive amide compound, and applying the polymer to selectedareas of the gas-expandable material.

15. The method of claim 11 which includes the step of applying a thinlayer of a transparent vinyl-chloride resin plastisol onto the surfaceof the treated vinylchloride resin prior to expansion, whereby onsubsequent heating, the transparent vinyl-chloride resin will fuse toform a wear-resistant transparent top surface layer.

16. The chemically embossed product produced by the method of claim 11.

2. The method of claim 1 wherein the reactive polymer is avinyl-chloride resin or acrylic resin, an alkyl resin or vinyl-acrylicresin, or an epoxy resin.
 3. The method of claim 1 wherein theheat-reactive compound is an amide.
 4. The method of claim 3 wherein theheat-reactive compound is an amide selected from the group consisting ofmelamine-formaldehyde resin, dicyanamide or hexamethoxymethylmelamine.5. The method of claim 1 wherein the thermoplastic resinous material isa plasticized vinyl-chloride resin which contains a chemical blowingagent therein.
 6. The method of claim 1 wherein the heat-reactivecompound is present in an amount of from about 0.1 to 15 phr of thepolymer, and the polymer contains from about 0.5 to 25 phr of thereactive groups.
 7. The method of claim 1 which includes applying thepolymer and heat-reactive compound to the selected areas in a liquidprinting composition.
 8. The method of claim 1 wherein cross-linking ofthe heat-reactive compound and the polymer occurs at a temperature offrom 50* to 140* C.
 9. The method of claim 1 which includescross-linking the polymer with the heat-reactive compound in thepresence of an acid catalyst in an amount of from about 0.05 to 2.0 phr.10. The cellular chemically embossed product produced by the method ofclaim
 1. 11. A method of preparing a cellular embossed thermoplasticresin, which methoD comprises: a. applying to a selected area of agas-expandable gelled vinyl-chloride resin sheet material avinyl-chloride polymer containing reactive hydroxyl, carboxyl or amidegroups, and a heat-reactive amide compound which will react with thegroups to cross-link the polymer, and to reduce the thermoplasticity ofthe gas-expandable vinyl-chloride resin in the selected areas; and b.heating the gas-expandable vinyl-chloride resin to a temperature toeffect the cross-linking of the vinyl-chloride polymer, the decomposingof the blowing agent and the fusing of the expanded vinyl-chlorideresin, thereby producing a chemically embossed cellular product.
 12. Themethod of claim 11 which includes applying the polymer and theheat-reactive amide cross-linking compound in a liquid plastisolcomposition to the surface of the gelled gas-expandable thermoplasticresin material.
 13. The method of claim 11 which includes incorporatingthe polymer in the gas-expandable thermoplastic resin material andtreating selected areas with the heat-reactive amide compound.
 14. Themethod of claim 11 which includes incorporating in the gas-expandablethermoplastic resin material a cross-linking amount of the heat-reactiveamide compound, and applying the polymer to selected areas of thegas-expandable material.
 15. The method of claim 11 which includes thestep of applying a thin layer of a transparent vinyl-chloride resinplastisol onto the surface of the treated vinyl-chloride resin prior toexpansion, whereby on subsequent heating, the transparent vinyl-chlorideresin will fuse to form a wear-resistant transparent top surface layer.16. The chemically embossed product produced by the method of claim 11.